"...For the first time, Interbike will open its doors to the public with the all new Northstar Free-Ride Festival powered by Interbike. The festival will take place at Northstar California Resort in North Lake Tahoe, September 14-16 , 2018. The event will kick off Friday night and will go through Su...

I will fill this in when I get home, but...I just wanted to make sure people could make plans as soon as possible, this event is only about four months away, and it is in a new location... Northstar California Resort in North Lake Tahoe Free-Ride Festival (Fri, Sat, Sun) September 14-16 Northstar Ca...

The Tesla cars and the Chevy Volt charge to 4.05V per cell, and their packs are under warranty, while costing many thousands of dollars. I'm not saying there is anything wrong with charging to 3.9V, but there likely isn't much of a benefit, if any...

There are many reasons I am a fan of 13S / 14S, and one of them is that...in a temporary power outage, they can run a nominal 48V inverter to provide 130V AC... Also, 15S is very rare, if you decide you truly want that, then you will likely need to build your own pack. Not impossible, but simply a m...

I haven't found any prototyping research data that has been published yet, but...the EV battery packs with the longest warranties have been using active cooling. On another related note, many square flat foil packs have been using compression cases to reduce any developing puffiness from creating lo...

The raw parts aren't too expensive, and assembling them is fairly quick once you get set up to do it. The only PITA is machining the holes and threads in the copper rods, so...I'm trying to figure out what my time is worth. Lets say...$49 to ES customers in the USA/Canada. PM your mailing address, a...

Sure. If you want a longer cable, I'd recommend you exercise caution, because that can increase the inductance. These are cut in half from a one meter section, so each one of the two cables is 1/2 meter long. This is the longest I would recommend that spot-welding cables should be (shorter is better...

This is the current version of the cables when purchasing a unit from me in the US. The solid copper rod is C14500 (7/16ths in diameter) which has a tiny amount of Tellurium in it to make it easy to machine ($1 per inch if purchased in bulk). Conductivity is still 93/100 of pure soft copper, but muc...

With half the ducts blocked off, units 2 + 3 don't have to work real hard as they cool the east side I did this too, to save on AC because I had two extra bedrooms I only used for storage, and it worked. However... when winter came, the heater would come on for a minute, and then just shut off (blo...

I would advise you to consider a geared hubmotor for the front wheel. As to the rear wheel, use a motor that is as powerful as you like. Also, be aware that simply adding a motor doesn't add power. Your battery may be maxed-out on the existing motor, so adding a second one will mean that splitting t...

Liquid-cooled electrodes would be simple to design, but a pain to construct. Copper pipe conducts liquid and also current. I've seen a resistance soldering transformer with 2 turns on the output (2,000A?) that was made from copper tubing (with insulation, of course). The two ends were terminated wit...

The college students at the Purdue University EV Kart race team have contacted me, asking for advice. They are having some issues with programming the controller, and are currently getting only 49A to the motor, and the system should provide much more than that. Sevcon Gen4 motor controller controll...

Equal current sharing is good, but I am not too worried about being exactly precise at every stage. I have a few suggestions, some of which may prove helpful. For common frame of reference, this is a triangle shaped 13S pack, and all P-strings are connected in the normal fashion except ...between P-...

Also, if you buy a low-powered kit and decide you want something with more capabilties, almost nobody will want to buy the low-powered kit from you. If you buy a kit that is more powerful than you want?...you might take a haircut on the price, but...at least you can sell it for something. Recently M...

I think there's an untapped market for the 20-inch all-in-one Magic Pies (and similar cast motor/wheels), when mounted on a BMX for a teen, or the rear wheel of a cargobike (ODK-II, Edgerunner, Madsen). I am not personally interested in trying it out, but if someone gave me one for free, I'd mount i...

Is it worth it?...it depends... If you are using a 1,000W MXUS with the aluminum stator-core, and it is providing the performance that you want while staying cool enough that it isn't in danger of overheating, then...there is no need to upgrade to a heavier or more expensive hubmotor. However, there...

in a hubmotor you want the fluxgap diameter as large as possible to maximize torque. for a given o/a housing diameter this means the spm radial outrunner owns the high ground (slightly) compared to afpm. IF...a common radial outrunner (such as a DD hubmotor) has the same diameter and thickness as a...

The place where adding supercapacitors to a battery would help the most (IMHO) is a DD hubmotor ebike on fairly flat land. On a long downhill, the SC's would be "filled" in a short amount of time, and then the rest of the downhill, any further regen harvesting would be limited by the batteries abili...

My wife finally started taking some, and her joints don't hurt anymore (inflammation reduction?). With reduced joint soreness, she now sleeps deeper and longer, so...she has more energy and is happier (from both the reduced soreness and also increased sleep quality). I had suggested to try ACV about...

If this wasn't from one of the big players, I'd immediately call BS. But..Toshiba is a "real deal" company. They are claiming 5,000 cycles and still delivers 90% of the new battery range. I'd be happy going from 1,000 cycles to 2,000 cycles, so,..this is pretty huge. I also like how the test cells h...